Blue Energy: Harnessing Generated Energy Where River Water Meets Sea Water, Potential Power Supply For World's Demands
There is untapped energy created when water from our rivers meets water from the sea along the shorelines of nations. Harnessing the generated energy of this mixture is now in development by researchers and scientists to further explore its application in societies and industries. These are what scientists call "The Blue Energy".
Researchers from the Penn State Environmental Engineering Department led by Christopher Gorski, Assistant Professor in Environmental Engineering, says that the team's target is to harvest energy where the river and sea meet. Blue energy depends on the difference in salt concentrations between the mixture of the two bodies of water.
Gorski adds that the harnessing of Blue energy from these waters could deliver 40 percent of the world's power requirement. Two available methods of energy capture parallel to this energy generation project available are pressure retarded osmosis and the reverse electrodialysis. These two famous methods are not so successful in the attempt to harness the generated energy.
Pressure retarded osmosis is so far the best method in terms of how much blue energy can be harnessed in this process. The most common method allows the mixed water to pass through the semipermeable membranes rejecting the salt. The osmotic pressure that develops in the process creates energy that is harnessable by turning turbines. However, when water passes through the membrane, the tendency of bacterial growth is imminent and the particles get stuck, hindering the passage of water through them due to the minute size of its holes, reports BBC.
The method of reverse electrodialysis utilizes electromagnetic gradients creating the voltage across the ion exchange membranes. In this method, either positively or negatively charged ions are allowed passage through the cation exchanger. Salt goes through and not the water. The process cannot harness much energy, unlike the pressure retarded osmosis.
The latest method of harnessing generated energy is now in exploration by Gorski and his team. The method is called "Capacitive Mixing" (CapMix) capturing the voltage generated when two bodies of water with different salt gradients collide. But like the process of reverse electrodialysis, it also generates little Blue Energy.
The team consequently found a method or methods to harness generated energy along their field of exploration. They combined the reverse electrodialysis and the capacitive mixing methods thereby discovering that the mixture of these processes produces more blue energy for harvesting, reports Science Daily.
The potential of the discovery is so huge that it could supply the lack of energy that the world demands. Gorski and his team said that they are now in the process of stabilizing their newly found method in blue energy for further application on a larger scale.